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author | Bruno Victal <mirai@makinata.eu> | 2023-03-08 01:22:09 +0000 |
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committer | Ludovic Courtès <ludo@gnu.org> | 2023-03-13 15:08:35 +0100 |
commit | 830497941526ac7320dcd4c5bb545ce9a040d1b1 (patch) | |
tree | 0abaaab99b3c2f42a764acb49ff46b7c6b2a7674 /doc | |
parent | 3c40dfe2851dd4ef48d2711f9f3531c06afbe1f2 (diff) | |
download | guix-830497941526ac7320dcd4c5bb545ce9a040d1b1.tar.gz |
doc: Use @defmac and @defspec for macros.
* doc/guix.texi (package Reference, Defining Package Variants) (Build Utilities, The Store Monad, G-Expressions, operating-system Reference) (Service Reference, Complex Configurations): Use @defmac and @defspec for macros. Signed-off-by: Ludovic Courtès <ludo@gnu.org>
Diffstat (limited to 'doc')
-rw-r--r-- | doc/guix.texi | 97 |
1 files changed, 47 insertions, 50 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index 539490d69b..39932d5aad 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -7781,7 +7781,7 @@ automatically corrected. @end table @end deftp -@deffn {Scheme Syntax} this-package +@defmac this-package When used in the @emph{lexical scope} of a package field definition, this identifier resolves to the package being defined. @@ -7801,7 +7801,7 @@ cross-compiling: @end lisp It is an error to refer to @code{this-package} outside a package definition. -@end deffn +@end defmac The following helper procedures are provided to help deal with package inputs. @@ -8160,7 +8160,7 @@ from the @code{inputs} field of @code{gdb}. The @code{modify-inputs} macro is a helper that can prove useful anytime you want to remove, add, or replace package inputs. -@deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses} +@defmac modify-inputs inputs clauses Modify the given package inputs, as returned by @code{package-inputs} & co., according to the given clauses. Each clause must have one of the following forms: @@ -8195,7 +8195,7 @@ The example below replaces the @code{guile} package from the inputs of The last type of clause is @code{append}, to add inputs at the back of the list. -@end deffn +@end defmac In some cases, you may find it useful to write functions (``procedures'', in Scheme parlance) that return a package based on some @@ -10164,7 +10164,7 @@ such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and @command{sed}. They complement Guile's extensive, but low-level, file system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}). -@deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{} +@defmac with-directory-excursion directory body @dots{} Run @var{body} with @var{directory} as the process's current directory. Essentially, this macro changes the current directory to @var{directory} @@ -10173,7 +10173,7 @@ guile, GNU Guile Reference Manual}). It changes back to the initial directory when the dynamic extent of @var{body} is left, be it @i{via} normal procedure return or @i{via} a non-local exit such as an exception. -@end deffn +@end defmac @defun mkdir-p dir Create directory @var{dir} and all its ancestors. @@ -10205,8 +10205,8 @@ symlinks. Don't follow mount points either, unless @var{follow-mounts?} is true. Report but ignore errors. @end defun -@deffn {Scheme Syntax} substitute* @var{file} @ - ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{} +@defmac substitute* file @ + ((regexp match-var@dots{}) body@dots{}) @dots{} Substitute @var{regexp} in @var{file} by the string returned by @var{body}. @var{body} is evaluated with each @var{match-var} bound to the corresponding positional regexp sub-expression. For example: @@ -10232,7 +10232,7 @@ they are all subject to the substitutions. Be careful about using @code{$} to match the end of a line; by itself it won't match the terminating newline of a line. -@end deffn +@end defmac @subsection File Search @@ -10393,7 +10393,7 @@ manipulate alists. The @code{(guix build utils)} module complements those with tools written with build phases in mind. @cindex build phases, modifying -@deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{} +@defmac modify-phases phases clause@dots{} Modify @var{phases} sequentially as per each @var{clause}, which may have one of the following forms: @@ -10406,7 +10406,7 @@ have one of the following forms: Where every @var{phase-name} above is an expression evaluating to a symbol, and @var{new-phase} an expression evaluating to a procedure. -@end deffn +@end defmac The example below is taken from the definition of the @code{grep} package. It adds a phase to run after the @code{install} phase, called @@ -11193,16 +11193,16 @@ build a file-like object (@pxref{Using Guix Interactively}). The main syntactic forms to deal with monads in general are provided by the @code{(guix monads)} module and are described below. -@deffn {Scheme Syntax} with-monad @var{monad} @var{body} ... +@defmac with-monad monad body @dots{} Evaluate any @code{>>=} or @code{return} forms in @var{body} as being in @var{monad}. -@end deffn +@end defmac -@deffn {Scheme Syntax} return @var{val} +@defmac return val Return a monadic value that encapsulates @var{val}. -@end deffn +@end defmac -@deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ... +@defmac >>= mval mproc @dots{} @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic procedures @var{mproc}@dots{}@footnote{This operation is commonly referred to as ``bind'', but that name denotes an unrelated procedure in @@ -11221,12 +11221,10 @@ in this example: @result{} 4 @result{} some-state @end lisp -@end deffn +@end defmac -@deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @ - @var{body} ... -@deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @ - @var{body} ... +@defmac mlet monad ((var mval) @dots{}) body @dots{} +@defmacx mlet* monad ((var mval) @dots{}) body @dots{} Bind the variables @var{var} to the monadic values @var{mval} in @var{body}, which is a sequence of expressions. As with the bind operator, this can be thought of as ``unpacking'' the raw, non-monadic @@ -11240,9 +11238,9 @@ expression, and its result will become the result of the @code{mlet} or @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let} (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}). -@end deffn +@end defmac -@deffn {Scheme System} mbegin @var{monad} @var{mexp} ... +@defmac mbegin monad mexp @dots{} Bind @var{mexp} and the following monadic expressions in sequence, returning the result of the last expression. Every expression in the sequence must be a monadic expression. @@ -11250,21 +11248,21 @@ sequence must be a monadic expression. This is akin to @code{mlet}, except that the return values of the monadic expressions are ignored. In that sense, it is analogous to @code{begin}, but applied to monadic expressions. -@end deffn +@end defmac -@deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ... +@defmac mwhen condition mexp0 mexp* @dots{} When @var{condition} is true, evaluate the sequence of monadic expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When @var{condition} is false, return @code{*unspecified*} in the current monad. Every expression in the sequence must be a monadic expression. -@end deffn +@end defmac -@deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ... +@defmac munless condition mexp0 mexp* @dots{} When @var{condition} is false, evaluate the sequence of monadic expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When @var{condition} is true, return @code{*unspecified*} in the current monad. Every expression in the sequence must be a monadic expression. -@end deffn +@end defmac @cindex state monad The @code{(guix monads)} module provides the @dfn{state monad}, which @@ -11585,8 +11583,8 @@ package available on the build side, here's how you would do it: The syntactic form to construct gexps is summarized below. -@deffn {Scheme Syntax} #~@var{exp} -@deffnx {Scheme Syntax} (gexp @var{exp}) +@defmac #~@var{exp} +@defmacx (gexp @var{exp}) Return a G-expression containing @var{exp}. @var{exp} may contain one or more of the following forms: @@ -11640,9 +11638,9 @@ Like the above, but refers to native builds of the objects listed in G-expressions created by @code{gexp} or @code{#~} are run-time objects of the @code{gexp?} type (see below). -@end deffn +@end defmac -@deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{} +@defmac with-imported-modules modules body@dots{} Mark the gexps defined in @var{body}@dots{} as requiring @var{modules} in their execution environment. @@ -11664,9 +11662,9 @@ path, and the last one is created from the given file-like object. This form has @emph{lexical} scope: it has an effect on the gexps directly defined in @var{body}@dots{}, but not on those defined, say, in procedures called from @var{body}@dots{}. -@end deffn +@end defmac -@deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{} +@defmac with-extensions extensions body@dots{} Mark the gexps defined in @var{body}@dots{} as requiring @var{extensions} in their build and execution environment. @var{extensions} is typically a list of package objects such as those @@ -11676,7 +11674,7 @@ Concretely, the packages listed in @var{extensions} are added to the load path while compiling imported modules in @var{body}@dots{}; they are also added to the load path of the gexp returned by @var{body}@dots{}. -@end deffn +@end defmac @defun gexp? obj Return @code{#t} if @var{obj} is a G-expression. @@ -11960,8 +11958,8 @@ the second case, the resulting script contains a @code{(string-append @dots{})} expression to construct the file name @emph{at run time}. @end defun -@deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{} -@deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{} +@defmac let-system system body@dots{} +@defmacx let-system (system target) body@dots{} Bind @var{system} to the currently targeted system---e.g., @code{"x86_64-linux"}---within @var{body}. @@ -11984,9 +11982,9 @@ spliced into the gexp depends on the target system, as in this example: (error "dunno!")))) "-net" "user" #$image) @end lisp -@end deffn +@end defmac -@deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp} +@defmac with-parameters ((parameter value) @dots{}) exp This macro is similar to the @code{parameterize} form for dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU Guile Reference Manual}). The key difference is that it takes effect @@ -12003,7 +12001,7 @@ for a given object: The example above returns an object that corresponds to the i686 build of Coreutils, regardless of the current value of @code{%current-system}. -@end deffn +@end defmac Of course, in addition to gexps embedded in ``host'' code, there are @@ -16654,7 +16652,7 @@ is that only @code{root} and members of the @code{wheel} group may use @end table -@deffn {Scheme Syntax} this-operating-system +@defmac this-operating-system When used in the @emph{lexical scope} of an operating system field definition, this identifier resolves to the operating system being defined. @@ -16672,7 +16670,7 @@ the definition of the @code{label} field: It is an error to refer to @code{this-operating-system} outside an operating system definition. -@end deffn +@end defmac @end deftp @@ -40595,8 +40593,8 @@ standard list combinators such as @code{map} and @code{fold} to do that @code{modify-services} simply provides a more concise form for this common pattern. -@deffn {Scheme Syntax} modify-services @var{services} @ - (@var{type} @var{variable} => @var{body}) @dots{} +@defspec modify-services services @ + (type variable => body) @dots{} Modify the services listed in @var{services} according to the given clauses. Each clause has the form: @@ -40629,7 +40627,7 @@ Such a clause removes all services of the given @var{type} from @xref{Using the Configuration System}, for example usage. -@end deffn +@end defspec Next comes the programming interface for service types. This is something you want to know when writing new service definitions, but not @@ -41105,8 +41103,7 @@ procedures that take some kind of Scheme value and returns a G-expression (@pxref{G-Expressions}), which should, once serialized to the disk, return a string. More details are listed below. -@deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @ -@var{clause2} ... +@defmac define-configuration name clause1 clause2 @dots{} Create a record type named @code{@var{name}} that contains the fields found in the clauses. @@ -41216,9 +41213,9 @@ macro which is a shorthand of this. (string "test") "Some documentation.")) @end lisp -@end deffn +@end defmac -@deffn {Scheme Syntax} define-maybe @var{type} +@defmac define-maybe type Sometimes a field should not be serialized if the user doesn’t specify a value. To achieve this, you can use the @code{define-maybe} macro to define a ``maybe type''; if the value of a maybe type is left unset, or @@ -41270,7 +41267,7 @@ whether its value is set or not. maybe-symbol "Docstring.")) @end lisp -@end deffn +@end defmac @defun maybe-value-set? value Predicate to check whether a user explicitly specified the value of a |